1. Field of the Invention
This invention relates to antiperspirant compositions, and more particularly, to new and improved antiperspirant compositions which leave a reduced visible residue on the skin of the user.
2. Description of the Prior Art
Antiperspirant compositions are well known in the art. See, e.g., U.S. Pat. Nos. 4,985,238; 5,302,381; 5,376,362; 5,417,963; 5,482,702; and 5,486,355. The active antiperspirant ingredient in such compositions usually is an inorganic compound, e.g., an aluminum, zirconium, or zinc salt such as an aluminum zirconium tetrachlorohydrate complex with glycine.
Many solid antiperspirant compositions have been described in the chemical and cosmetic literature. These compositions generally tend to fall into one of two classes: emulsion sticks and suspensoid sticks. Emulsion sticks contain a solution of the antiperspirant active incorporated into the stick via an emulsion. Although emulsion sticks may be desirable in certain respects, they tend to be unstable, have poor aesthetics (e.g., are overly hard, greasy or sticky), and leave a visible residue on the skin after use. Suspensoid sticks contain the powdered antiperspirant active suspended in the stick without the use of water or an emulsion. While suspensoids tend to be stable, they may be brittle and hard and, more importantly, they tend to leave an unsightly white chalky residue on the skin after application. This residue is not only aesthetically displeasing to the user, but can also discolor clothing. It has now been discovered that when a phenylethyl or benzyl ester is incorporated into water-free suspensoid antiperspirant stick compositions, they exhibit excellent antiperspirant efficacy and aesthetics, while leaving reduced visible residue on the skin of the user.
Accordingly, it is an object of this invention to provide an antiperspirant composition which leaves a reduced visible residue on the skin of the user.
Another object of the invention is to provide an antiperspirant composition containing an additive preferably having a refractive index which substantially matches the refractive index of the white, chalky residue formed after use thereby significantly reducing the appearance of the visible white, chalky residue on the skin of the user.
Still another object of this invention is to provide an antiperspirant composition which includes an active antiperspirant ingredient and a phenylethyl, benzyl or substituted benzyl ester as additive therein, which is an aryl carboxylic ester of 2-phenylethyl alcohol, 1-phenylethyl alcohol or benzyl alcohol, preferably having a refractive index which substantially matches the refractive index of the white, chalky residue thereby reducing the visible white appearance of the residue.
These and other objects and features of the invention will be made apparent from the following description thereof.